Apparatus for trimming shoe soles and heels

ABSTRACT

Method and apparatus for trimming excess sole and/or heel material during the manufacturing of shoes. A template conforming to the desired configuration of the sole and heel cooperates with a special heated cutting element to cause the knife element to follow the periphery of the template and cut off the excess material. The template, made of a rigid, hard, insulating and heat-resisting material, is adapted by means of a plurality of sharpened pin members for mounting directly on the sole material.

United States Patent -191 Egtvedt et al.

[451 Apr. 9, 1974 APPARATUS FOR TRIMMING SHOE SOLES AND HEELS [75] Inventors: Robert B. Egtvedt, Comstock Park;

Anthony J. Wolfer, Grand Rapids; Edward V. Connors, Jr., Grand Rapids; Jerry L. BoomersfGran'd Rapids, all of Mich.

[73] Assignee: Wolverine World Wide, Inc.,

Rockford, Mich.

22 Filed: May 5,1972

21 Appl. No.: 250,735

[52] US. Cl. 12/87 [51] Int. Cl A43d 7/00 [58] Field of Search 12/86, 86.5, 86.7, 87,

[56] References Cited UNITED STATES PATENTS Cunningham 12/] R Jacobson 219/21 Green 12/1 R 2,296,517 9/1942 2,615,111 10/1952 Paquette et al..... 219/19 1,383,023 6/1921 Preston l2/86.5 3,134,998 6/1964 Kunze et al l2/86.7

FOREIGN PATENTS OR APPLICATIONS 878,562 10/1961 Great Britain [2/85 Primary Examiner-Patrick D. Lawson Attorney, Agent, or Firm-Price, Heneveld, l-luizenga & Cooper [5 7] ABSTRACT Method and apparatus for trimming excess sole and/or heel material during the manufacturing of, shoes. A template conforming to the desired configuration of the sole and heel cooperates with a special heated cutting element to cause the knife element to follow the periphery of the template and cut off the excess material. The template, made of a rigid, hard, insulating and heat-resisting material, is adapted by means of a plurality of sharpened pin members for mounting directly on the sole material.

10 Claims, 6 Drawing Figures APPARATUS FOR TRIMMING SHOE SOLES AND HEELS BACKGROUND OF THE INVENTION In the manufacture of shoes, boots, and the like, the sole and heel portions fixed to the upper are usually made slightly oversize with respect to the upper and must be trimmed to size. Various methods and apparatus have been devised for such trimming operations. These usually include the use of a reciprocating trimming knife and guide means for the knife which follow about previously shaped portions of the shoe such as the welt. One such prior art device of this type is illustrated in U. S. Pat. No. 1,657,632. This type of device is fairly complicated as it requires rather involved and special clamping fixtures, blade-holding mechanisms and guide mechanisms to ensure that the sole is trimmed to the desired configuration without damage to the upper. Moreover, these conventional devices do not readily lend themselves to cutting of plantation crepe sole materials.

SUMMARY OF THE INVENTION The present invention provides a simplified method and apparatus for trimming shoe sole and heel materials in its provision of a quickly and readily attachable template or pattern which defines the outline of the desired completed sole and heel and in the provision of a heated cutting means to follow the contour of the pattern while cutting and trimming excess material from the sole and heel. The invention is particularly applicable to the trimming of plantation crepe materials which do not readily lend themselves to processing by conventional cutting or sawing techniques.

Accordingly, it is a primary object of the present invention to provide a method and apparatus for trimming shoe soles and heels in a quick and convenient manner, especially those made of plantation crepe ma terial.

It is another object of the present invention to provide a method and apparatus for trimming shoe soles and heels utilizing a heated cutting element. It is yet another object of the present invention to provide a method and apparatus for trimming shoe soles and heels utilizing a template or pattern which is quickly and readily attachable directly to the sole of the shoe.

Another object of this invention provides a method and apparatus for cutting a bevel or wedge on a shoe heel.

Another object of this invention is to provide a novel method and apparatus for trimming shoe soles with a combination directly-attached template and a contained heated knife.

Other important objects, advantages, and features of the present invention will become readily apparent to those skilled in the art upon reading the foregoing specification and with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a perspective view of the apparatus of the present invention;

FIG. 2 is a side view of the apparatus shown in FIG.

FIG. 3 is a cross-sectional view of the heated knife assembly taken along the plane III--III of FIG. 1;

FIG. 4 is a side view of the template of the present invention mounted on the sole of a shoe;

FIG. 5 is a top plan view of the template shown in FIG. 4; and

FIG. 6 is a perspective view of a heel wedging fixture.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings, and in particular to FIGS. 1 and 2, the apparatus generally illustrated by the numeral 10 will be described in detail. Basically, the shoe-trimming apparatus 10 includes a flat planar base surface 12, a heated knife subassembly l4,.and a controller 16 for the knife assembly. The knife assembly 14 includes a knife 14 which extends through and perpendicular to the base surface 12. The base includes a mounting plate 18 for convenient mounting on a work bench or the like. The base plate is held in a spaced-apart position from the mounting plate 18 by a plurality of upstanding leg members 20 suitably secured to surface 12 and base plate 18 by means of screws or the like.

The knife 14 is held in its perpendicular position by supports at its upper and lower ends above and below platform 12 respectively. Specifically, a vertical support member 22 fixed at one side of flat platform or surface 12 cooperates with arms 24 and 26 to form a mount, that is, extending inwardly from the vertical support 22 toward the center portion of surface 12 and holding knife 14 is an upper arm member 24 and lower arm member 26. The knife 14 is secured between these upper and lower arm members by screws 28 passing through slots 30 (FIG. 3) in the knife 14 through an insulator 27 and threadably received in the ends of the arms 24 and 26. As blade 14 is heated, its axial length increases slightly. Slots 30 at the connection with arm member 24 allow movement of the blade to thereby prevent warping. A guard or framework 29 surrounds the upper portion of the knife 14 to protect the operator.

Referring to FIG. 3, a cross-sectional view of the heated knife assembly 14 is illustrated in greater detail. The knife assembly 14 is preferably machined from beryllium copper or the like and includes a sharpened vertical edge portion 32 along one side thereof. An electrical heater 34 is mounted in a slot 36 machined in the surface of the knife assembly closely adjacent the edge 32 to heat the edge to an elevated temperature. The electrical heater may comprise one or a plurality of resistive heater elements of the type well known to those skilled in the art. The resistance elements are connected to the temperature controller 16 (FIGS. 1 and 2) by means of wires 38.

An important feature of the knife assembly 14 resides in the shape of the sharpened edge portion. Specifically, the portion of the knife receding from or behind sharpened edge 32 is divergent in a configuration forming a curvilinear concavity 33. The portion of the concavity immediately adjacent the edge is at a small acute angle relative to the backside of the knife while the remaining portions of the concavity flow outwardly from the edge and the backside generally transverse to the edge such that the material cut by the edge will be peeled away from the knife at a rather sharp angle.

Referring now to FIGS. 4 and 5, an oversize sole portion 51 having an oversize heel 50 secured thereto is shown positioned and attached to a template 52 by means of a plurality of pin members 54 located about the surface of the template and projecting into the sole. For convenience, the combined sole and heel portions of a shoe will sometimes be referred to as the shoe sole. The pin members 54 are sharpened or pointed such that they may be readily inserted into the sole material by pressing them together. In the preferred, most advantageous application of the invention, the sole 5] and heel 50 are formed of plantation crepe rubber somewhat oversized and requiring trimming to a finished size. The template 54 is shaped to the desired sole shape and size. Preferably, the template is constructed of melamine polymer, e.g., formaldehyde polymer or an equivalent phenolic polymer, e.g., phenol formaldehyde polymer, or the like, forming a hard, heatresistant and heat-insulating material. The template is not easily cut and therefore is not damaged by the knife nor does it interfere with the knife during trimming of the sole material but rather provides a smooth bearing surface for the knife to follow.

In operation, the template 52 is positioned on the sole 5] by means of the projecting pin members 54. The template assembly is then placed on the flat planar surface 12 (FIG. 1) of the trimmer assembly 14 such that the heated cutting edge 32 softens the material rendering it readily yieldable to the blade which bears against the template 52. The template is moved along the sharpened edge portion 32 to thereby cut and trim the sole material 51 to conform to the outer periphery of the template.

The heated knife assembly 14 is normally maintained at a constant temperature by means of the controller 16 connected through wires 38 to the heating element 34. The temperature controller is conventional in construction and preferably employs a thermocouple or sensing element 40 positioned in a recess adjacent the heated edge 32 of the knife assembly 14 to sense and control the temperature thereof by means of suitable switching mechanisms within the controller 16. The element 40 is connected to the controller 16 by wires 41. A temperature controller suitable for use with the present invention is available from Barber Colman Company, Industrial Instruments Division, Rockford, Ill., and commercially available as their model 72C modular temperature controller with thermocouple input and solid state switching.

The excess material is therefore quickly and accurately cut and peeled away from the periphery of the template as it is moved about the heated knife assembly. The edges of the template may also be beveled. Support member 22 may be tilted with respect to base plate 12 so that there is an angle between the base and the blade to produce a beveled edge on the sole material if desired.

Depending upon the particular shoe construction, the heel portion may be formed to have a slight angle or wedge cut thereon with respect to the sole material prior to fixing the heel to the sole. A heel wedging fixture 56 which may be utilized with the heated knife is illustrated in FIG. 6. An oversize heel 50 fonned of the same or similar material to that of the sole is placed in a fixture 56. The fixture includesa recessed portion 58 slightly larger than the outer periphery of the heel 50 and has a depth equal to the desired thickness of the heel. The face 60 of the fixture tapers in thickness from the back portion (corresponding to the back of the heel) downwardly toward the front at an angle. The particular angle, of course, may be varied depending upon the particular shoe style which is manufactured. With the sole 50 positioned in the recess 58, the face of the fixture is placed in abutting relationship with the heated knife and the wedge is cut by the knife in a manner as previously described in connection with the sole template. The heel wedging fixture may be constructed of the same or similar material to that of the sole template and if desired, may include a plurality of pin members 62 also similar to those shown in connection with the sole template to hold the heel in the recess 58 while cutting operations are performed.

While a preferred embodiment of the invention has been illustrated and described, it will be recognized to those skilled in the art that other embodiments and modifications of the invention incorporating the teachings hereof may be readily made in light of this disclosure. All modifications embodying the principles of this invention-are therefore considered as included in the appended claims unless these claims by their language expressly state otherwise.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. Apparatus for trimming excess material in the manufacture of shoes to a predetermined final configuration comprising:

a template having outer edge portions conforming to the desired configuration;

means for holding said template on said material in predetermined position; and

trimming means adapted to follow said edge portions of said template to remove said excess material, said trimming means having a sharpened edge portion and heating means for said portion whereby said heated sharpened edge portion softens said material rendering it readily yieldable to said trimming means.

2. The apparatus as defined in claim 1 wherein said means for holding said template on said sole includes a plurality of pin members fixed to said template extending therefrom and engageable with said sole material to prevent movement of said template with respect to said sole.

3. The apparatus as defined in claim 2 wherein said template is formed of hard heat-resisting insulating material.

4. The apparatus as defined in claim 3 wherein said template is formed of a hard, polymeric material.

5. The apparatus as defined in claim 1 wherein said trimming means has an elongated recess formed therein adjacent said sharpened edge portion and said heating means is an electrical resistance heating element positioned in said recess.

6. The apparatus as defined in claim 5 and further including control means for said heating element;

sensing means for sensing temperature variations of said edge;

and means connecting said sensing means and said control means to maintain a controlled temperature at said edge portion.

7.'The apparatus as defined in claim 1 wherein a portion of said trimming means receding from said sharpened edge is divergent in configuration forming a curvilinear concavity in said trimming means adjacent said cutting edge,

said wedge and follow the angular surface thereof to remove material from said heel forming said wedge, said trimming means having a sharpened edge portion and heating means for said portion 5 whereby said heated sharpened edge portion softens said material rendering it readily yieldable to said trimming means. 10. The apparatus as defined in claim 9 wherein said l0 fixture is formed of hard heat-resisting insulating material. 

1. Apparatus for trimming excess material in the manufacture of shoes to a predetermined final configuration comprising: a template having outer edge portions conforming to the desired configuration; means for holding said template on said material in predetermined position; and trimming means adapted to follow said edge portions of said template to remove said excess material, said trimming means having a sharpened edge portion and heating means for said portion whereby said heated sharpened edge portion softens said material rendering it readily yieldable to said trimming means.
 2. The apparatus as defined in claim 1 wherein said means for holding said template on said sole includes a plurality of pin members fixed to said template extending therefrom and engageable with said sole material to prevent movement of said template with respect to said sole.
 3. The apparatus as defined in claim 2 wherein said template is formed of hard heat-resisting insulating material.
 4. The apparatus as defined in claim 3 wherein said template is formed of a hard, polymeric material.
 5. The apparatus as defined in claim 1 wherein said trimming means has an elongated recess formed therein adjacent said sharpened edge portion and said heating means is an electrical resistance heating element positioned in said recess.
 6. The apparatus as defined in claim 5 and further including control means for said heating element; sensing means for sensing temperature variations of said edge; and means connecting said sensing means and said control means to maintain a controlled temperature at said edge portion.
 7. The apparatus as defined in claim 1 wherein a portion of said trimming means receding from said sharpened edge is divergent in configuration forming a curvilinear concavity in said trimming means adjacent said cutting edge.
 8. The apparatus as defined in claim 7 wherein the portion of said concavity immediately adjacent said cutting edge forms a small acute angle at said edge, said concavity flowing outwardly, generally transverse to said sharpened edge.
 9. Apparatus for cutting a wedge on a shoe heel during the manufacture of shoes comprising: a fixture having a recess formed therein adapted to receive oversize heel material, said fixture including a face portion tapering at an angle corresponding to the angle of the desired wedge; and trimming means adapted to abut the face portion of said wedge and follow the angular surface thereof to remove material from said heel forming said wedge, said trimming means having a sharpened edge portion and heating means for said portion whereby said heated sharpened edge portion softens said material rendering it readily yieldable to said trimming means.
 10. The apparatus as defined in claim 9 wherein said fixture is formed of hard heat-resisting insulating material. 